Control apparatus for the pattern drum of a knitting machine

ABSTRACT

A pattern drum is intermittently rotated forward or backward, by variable numbers of steps, by a control star rotor having uniformly spaced pins. A pair of pin engaging control members can be set to control such a pin for forward motion (by activating one member of the pair), or for backward motion (by activating the other member of the pair), or for zero motion (by deactivating both members). For these purposes, the control members rotate with an annular guide system past the control star and drum.

States atent 1 Scheffier et al.

[ 1 Sept. 18, 1973 CONTROL APPARATUS FOR THE PATTERN DRUM OF A KNITTINGMACHINE [75] Inventors: Ilolger Scheffler, Lichtenstein;

Konrad Bannehr, Leukersdorf; Ingo Ziprian, Gersdorf, all of Germany [73]Assignee: VEB Wirkmaschinenbau,

Karl-Marx-Stadt, Germany [22] Filed: Apr. 12, 1972 [21] Appl. No.:243,325

[52] U.S. Cl 66/50 B [51] Int. Cl D04b 9/00 [58] Field of Search 66/50B, 24, 25, 66/154, 156

[56] References Cited UNITED STATES PATENTS 3,416,332 l2/l968 Joseph66/50 B 3,587,253 6/1971 Guell 66/50 B Primary Examiner-Ronald FeldbaumAttorney-Albert C. Nolte, Jr. et al.

[57] ABSTRACT A pattern drum is intermittently rotated forward orbackward, by variable numbers of steps, by a control star rotor havinguniformly spaced pins. A pair of pin engaging control members can be setto control such a pin for forward motion (by activating one member ofthe pair), or for backward motion (by activating the other member of thepair), or for zero motion (by deactivating both members). For thesepurposes, the control members rotate with an annular guide system pastthe control star and drum. 7

9 Claims, 7 Drawing Figures Patented Sept. 18, 1973 3,759,069

3 Sheets-Sheet l T :1- l' mfg Patented Sept. 18, 1973 5 Sheets-Sheet 2Patented Sept. 18, 1973 3 Sheets-Sheet 5 CONTROL APPARATUS FOR THEPATTERN DRUM OF A KNITTING MACHINE BACKGROUND AND NATURE OF THEINVENTION For driving the pattern drum of a machine which producespattern knitwear, mechanisms have been used thus far which had seriousproblems and defects. In the first place, it always was difficult toturn the pattern drum by a step or steps of uniform angular length. Mostof the devices for limiting such a step were brakes; these are subjectto heavy wear and tear and therefore are in need of frequentandexpensive readjustment. Another problem is that, when the machineruns fast, jolts are encountered when starting or ending a turning step.I

The invention overcomes these difficulties by a new construction of theso-called control star and of the systems utilized for moving it. In apreferred embodiment of the invention this star has four pins. Two ofthem normally are held in an annular channel, which rotates relativethereto, while the other two ride on the outside of the channel. At onepoint the channel is interrupted by insertion of a star turningmechanism, comprising four pin engaging members. One or two of these areraised into engagement with successive pins of the star. If one of thesemembers is raised the star is turned by 90; if two are raised it isturned by 180. The drum is correspondingly promoted by one or twocontrol steps. Preferably, the pin engaging parts of the control membershave pin impact and pin guiding surfaces corresponding respectively tothe impact path of one pin and the corresponding motion of'afollowingpin, thereby preventing uncontrolled impact motions even in thecase of very rapid operation.

IN THE DRAWINGS FIG. 1 is an elevational sectional view of apparatusincorporating the invention, the section being taken along lines l1 inFIG} 3;

FIG. v2 is a fragmentary sectional view taken along lines 2-2 in FIG. 1;

FIGS. 3 6 are plan views of the apparatus showing successive positionsof relatively movable parts thereof; and

FIG. 7 is a top view of the apparatus.

DETAILED DESCRIPTION In the preferred embodiment described herein actualrotary motion is performed by annular groove or channel 21 and controlmembers 17 to 20 thereof, while pattern drum land control star 12 arestationary, the motion of the first-mentioned parts being performed inthe direction of arrow A, shown in each plan view figure. In order toavoid the need for an over-sized illustration, we assume that theobserver moves along with the parts 17 to 21 which accordinglyappear'i'n the same position in the successive plan view figures, whileaccordingly parts 1 and 12 appear to move in a direction opposite to thearrow A.

Pattern drum 1, best shown in FIG. 1, is mounted on vertical shaft 2 forthe purpose of turning the drum in successive steps. The turning stepsof the drum are performed in order to reciprocate pushers which in turnmove knitting needles according to a predetermined program for theproduction of pattern fabric; these lat ter parts and products need notbe shown herein, as

I art.

many types of them are known to persons skilled in the A simple gearmechanism described hereinafter connects drum I with control star 12 sothat this star can turn the drum. The star is built in the form of acircular plate P, having four pins 13 to 16 secured to the peripherythereof at uniform angular distances from one another and projecting ashort distance from the underside of the plate.

In a location generally below these pins there are provided four controlmembers 17 to 20. One of them (19) is shown only in part in FIG. I. Theyare vertically movable between certain limits, by mechanisms known bypersons skilled in the art, in a guide system shown only schematicallyas G (FIGS. 1 and 2). As already indicated, these members are insertedas part of annular channel 21. Control members 17, 18 are generallyinside the circle of this channel while the other two are outside ofthis circle (FIGS. 3 to 6).

When all control members 17 to 20 are in their lower position, none ofthem engages any of pins 13 to 16. Therefore, in such position of thecontrol members there occurs no motion of control star 12 and patterndrum 1 but the control members merely pass the control star.

The operation is different when, for example, control member 17 islifted into the position shown in FIG. 1. This member then encounterspin surfaces of the control star during the relative motion of theseparts and turns the star and thereby the drum. If both members 17 and 18are in such position (FIG. 3) as shown, thestar is turned by twosuccessive steps, in the rotary direction indicated byarcuate arrow B inFIG. 4. On the other hand, if inner control members 17, 18 were loweredand outer control member 19 and/or 20 were raised, the star would beturned to make one or two' steps in the opposite rotary direction.

According to the invention two diametrically opposite pins of thecontrol star, forexample pins 13 and 16 according to FIG. 3, arenormally guided in annular groove 21A of guide channel 21. This guidanceprotects control star 12 and pattern drum 1 against any accidental, forexample vibratory turning throughout the normal operation of themachine, particularly since the star is additionally guided by pins l4,15 which slide or run along the outsides of channel 21.

The successive relative motions will be understood readilyonconsideration of FIGS. 3 to 6. As shown in FIG. 3, control star 12 stillis guided by channel 21.

However, the channel is aboutto free the pins of the star for rotarymotion, in the rightward travel A of channel and control members, andthere is a short gap C between the illustrated leftwardly facing end ofthe channel and the opposite right-hand end of the control members 17 to20.

'As these members come closer to the control star, FIG. 4, an impactsurface 22, upstanding from a right surface part of raised controlmember 18, encounters pin 15 and initiates clockwise turning B of thecontrol star. No interfering impact occurs on opposite control member20, which is in low position and does not engage any of the pins of thecontrol star.

As shown in FIG. 5, pin 15 has performed part of its clockwise motionand thereby pin 13 has engaged upstanding contact surface 23, the twosurfaces 22, 23 being the two sides of an impact and control lug 23A onthe upper surface of control member 18. On further leftward relativemotion of star 12 coupled with clockwise rotary motion thereof, pin 15is driven further downward while pin 13 slides along surface 23. In thisway any serious vibration of star 13 is prevented by lug 23A, as it waspreviously presented by the walls of channel 21.

Control members 17 and 18 are of similar surface structure. In order toavoid useless repetitions, further relative motions will be discussedwith reference to control member 17 and guide lug 25 upstanding from aleft part of the upper surface thereof (FIG. and 6). (It will beunderstood similar motions occur along guide lug 24 in the left part ofcontrol member 18. It will also be understood that, when the controlstar left member 18, a further impact occurred on lug 23B of raisedmember 17, producing a further partial clockwise rotation as alreadydescribed. The impact at 18 has brought pin into a position aligned withthe circular center line D of guide groove 21, and in the relativemotion of the control star the centered pin 15 then was preceded by pin14 also aligned with this center line. The further impact at controlmember 17 imparted further clockwise rotation to the control star). Pins13, 14 then are, respectively, in positions inside and outside guide lug25, as shown in FIG. 6. Directly thereafter these pins reach guidegroove 21A again, wherein they move in the same way that was shown inFIG. 3, except that they have been turned clockwise by 180.

If only one of control members 17, 18 had been raised, the star wouldhave been turned 90. As already indicated, similar turning by one or twosteps, but in counterclockwise direction, could be performed by raisingone or two outer control members 19, 20. Obviously the raising andlowering control for the control members, not shown herein, must be suchthat at no time inner and outer control members, for example 18, 20, areraised at the same time, since the mechanism would be broken by theimpact ensuing in that case.

It will be understood that the forward or backward turning of controlstar 12 causes corresponding turning, preferably by fewer degrees, ofdrum 1 (FIG. 1). For this purpose, shaft 2 has a disk 3 secured theretowhich has upstanding pins 4; these are so received in drum 1 as to makethe drum rigid with the disk. The upper end of the drum has a disk 5,secured against rotation by a dowel 4A. Disk 5 is pressed downwards topress drum 1 against lower disk 3, by the bottom washer 6 of acompression spring 7, the upper end of which is retained by washer 8 ona coaxial top member 9 of shaft 2. Control star 12 has a shaft 12A whichat its upper end carries pinion l0, meshing with larger gear 10A. Thatgear is inserted between disk 3 and drum 1, to rotate them as the gearis rotated by control star pinion 10. Both shafts 2 and 12A are pivotedin a supprt 5 (also shown in FIG. 3, but omitted in FIGS. 4-6). In orderto avoid even the slightest, detrimental jolts of star 12, the shaft 12Ais guided in a bearing B depending from support S (FIG. I).

It will be understood that, when the knitting machine has a number ofpattern systems, each system can have a drum constructed in this sameway. In this case each system of course has a control star 12, while asingle annular groove 21 and a system of control members 17 to 20sufi'lces.

The new mechanism turns pattern drums in steps of exactly such length ashas been predetermined, even when relative motions of drum and controlmembers are very rapid. Regardless of speed, the new mechanism operateswithout any objectionable jolt. Persons skilled in the art willappreciate that it, at the same time, is no more complex than theearlier machines for the same purpose.

What is claimed is:

1. Apparatus for the control of a pattern drum in a knitting machine,particularly in a large circular knitting machine, comprising: a controlstar for the drum, said star having two pairs of pins secured to thestar and projecting from it; a substantially annular guide channelrotatable about its center, past the control star, and disposed tonormally keep one pair of mutually opposite pins of said star in thechannel and the other pair outside the same; and a control system on androtatable with said guide channel for turning the star by apredetermined angle when the control system encounters a pin of thestar.

2. Apparatus according to claim 1 wherein said guide channel is disposedto contact pins of said star, kept inside and one member outside thechannel.

3. Apparatus according to claim 1 wherein said control system has atleast one pair of control means, one for turning the star in onedirection and the other for turning it in the opposite direction.-

4. Apparatus according to claim 3 wherein said control system has asecond pair of control means, similar to the first pairs.

5. Apparatus according to claim 1 wherein said pins are uniformly spacedfrom one another.

6. Apparatus according to claim 3 wherein each control means has animpact surface for deflecting one of said pins and also has a guidesurface for guiding, during at least part of said deflecting, anotherone of said pins.

7. Apparatus according to claim 6 wherein said impact and guide surfaceshave such curvature as to slide along the respective pins, incident tothe pin motions produced by relative motions of the star and the controlsystem.

8. Apparatus according to claim 7 wherein each control means also hasguide means for guiding a pin of the impact-deflected star back intosaid channel.

9. Apparatus according to claim 1 wherein said guide channel has a shortgap adjacent said control system,

to provide space for turning said star.

i l i

1. Apparatus for the control of a pattern drum in a knitting machine,particularly in a large circular knitting machine, comprising: a controlstar for the drum, said star having two pairs of pins secured to thestar and projecting from it; a substantially annular guide channelrotatable about its center, past the control star, and disposed tonormally keep one pair of mutually opposite pins of said star in thechannel and the other pair outside the same; and a control system on androtatable with said guide channel for turning the star by apredetermined angle when the control system encounters a pin of thestar.
 2. Apparatus according to claim 1 wherein said gUide channel isdisposed to contact pins of said star, kept inside and one memberoutside the channel.
 3. Apparatus according to claim 1 wherein saidcontrol system has at least one pair of control means, one for turningthe star in one direction and the other for turning it in the oppositedirection.
 4. Apparatus according to claim 3 wherein said control systemhas a second pair of control means, similar to the first pairs. 5.Apparatus according to claim 1 wherein said pins are uniformly spacedfrom one another.
 6. Apparatus according to claim 3 wherein each controlmeans has an impact surface for deflecting one of said pins and also hasa guide surface for guiding, during at least part of said deflecting,another one of said pins.
 7. Apparatus according to claim 6 wherein saidimpact and guide surfaces have such curvature as to slide along therespective pins, incident to the pin motions produced by relativemotions of the star and the control system.
 8. Apparatus according toclaim 7 wherein each control means also has guide means for guiding apin of the impact-deflected star back into said channel.
 9. Apparatusaccording to claim 1 wherein said guide channel has a short gap adjacentsaid control system, to provide space for turning said star.